ESE's works engine tuner

[Lightbulb]

As far as piston breakage. Most often breakage that is caused by piston acceleration starts as cracks in the transfer cut outs. If the piston has no cutouts those related stress risers are eliminated. The stress on the rod and piston are greatest near the top of the stroke. Faster combustion properly timed would to some extent help reduce those stresses. (small effect and only under full throttle) 100 to 135cc kart engines with careful consideration's will give acceptable rod and bearing life at extended run periods of 20,000 or higher rpms. That is a long ways from 30,000rpms. BUT I do not recall it ever being stated that the Ryger makes its most usable power at 30,000rpm's. Just that it is capable of running to that high of rpm's. Maybe acceptable piston life will be in minutes not hours???? Kermit Buller

In model engines, the 1st sign of impending failure is the gudgeon pins flogging out , the other failure is piston collapse or a hole in the piston if run too lean.
It seems we are all looking for more complex things or arrangements rather than looking for more simple. Sometimes simple seems to be too simple and then we look at all the negatives we can think of,instead of the positive and the advantages of simple. If a conversion is done in a day or so, the same time as rebuilding an engine with a rod change, it can not be complicated in order to be done in that time frame.
Neil

[peewee]

hey frits in the photo with your hand over the engine top (previous pg), why is the carb not at the same angle as the cylinder inlet ? is it only because there isnt a suitable carb that can operate at that steep downward angle or is it some other reason ?

can anybody else make out whats just below the carb, the area where the carb would be if it was using the crankcase inlet ?

[MotleyCrue]

No, looking from the cylinder top down at the bore, you would see regular ports.Likewise looking through the exhaust port, all will look normal.
Neil

But if the piston is stepped and I moved the piston from top to bottom and looked in the exhaust port, I dont think that what I would see would be normal looking, or did I miss some info as to what would prevent me from seeing the step?

[Leed]

But if the piston is stepped and I moved the piston from top to bottom and looked in the exhaust port, I dont think that what I would see would be normal looking, or did I miss some info as to what would prevent me from seeing the step?

A KR-1 piston is 60mm long - the stroke is 50.6mm
If I look up the exhaust port at TDC - do you think I can see the last 10mm/bottom of the skirt?

Frits said that because it gives away nothing... sit in the exhaust what do you see nothing but skirt



"Even with the piston at BDC you would not notice that it is a Ryger engine... "

[MotleyCrue]

A KR-1 piston is 60mm long - the stroke is 50.6mm
If I look up the exhaust port at TDC - do you think I can see the last 10mm/bottom of the skirt?

I guess you have a point there.

[Flettner]

i expect you have already spun this crank set up with something attached externally?, obviously not under load. how did it go? (you may have posted these findings previously, sorry to ask again ) in reality i expect if its good enough for 17500-20000 rpm it would be job done

Breezy, I do have another crank system designed without a beam but that definitly stays in the draw for now, might be too embarrassing to show off
It allows for liner movement only, no centrifugal on the big end. Rod, bigend and piston can be one part, no gudgin pin at all. NO cams or cam rollers or cam tracks and is not single sided. BUT I would like to see it work before I open my big mouth!

[polinizei]

https://www.google.com/patents/DE102...IVxJMsCh0e0gMT

Passage 0023
Maybe in the rygerspacer is a simple transfer header contur, we usualy see in exhaust systems.


Passage 0026
Describes the effect of scavenging with higher speed.

[Leed]

could be made of 3 systems:
1. CYLINDER REED INDUCTION (top end)
2. '4T' BOTTOM END with 'reeded' inlet breather & 'reeded' crankcase outlet,
3. Pressure accumulator/receiver, for higher pressure charge injection

conventional Torque output is variable over a single stroke.
what IF it was more variable over two piston strokes...
if Tstroke2 = 2*Tstroke1 : every second stroke sequence Ts3 = Ts1
then Taverage = (Ts1 + Ts2)/2
mathematically you might get 70hp

^^^.....just a brain burp.... Ryger makes more power by sustaining near peak torque under increased revolutions

[JanBros]

to make 70hp at 30,000

it doesn't.
it makes 70BHP at 17.500 and is capable of revving 30.000 but for how long is still not known.

[Frits Overmars]

the head may be standard 2T but what screws into the sparkplug hole? see Frits' photo attached hiding air injection/ignition?

I already explained that, Leed. In the spark plug hole there is nothing but a spark plug. I just put my hand on the plug cap to program my body into remembering where that plug cap was, because I didn't want to hurt my elbow while driving. At that same instant a photo was taken that went all over the internet.
Because of the flood of far-fetched reactions to this first photo we decided to put our hands on the plug cap again. And it worked again, as your reaction proves

we see a standard alloy crown in mock up - doesn't mean it doesn't run with a ceramic one

There is no mock-up and I already stated that there are no ceramics.

if a light weight rod can be used then why is it shorter - is the short rod necessary must be to accommodate a linkage or modification of the stroke cycle

Already answered: a long rod can be used as well but it would make the engine higher.

Modena KZ1... removable insert built with thermally insulating material, to maintain mixture temperature and improve volumetric efficiency'
as wobbly has alluded, with every factor involved, perhaps it is blueprinted from a pool best achievable ideas. anyone remember theglobe.com

The removable insert in the Modena engine was an idea from my friend Roland Holzner, Modena's technical director.
The suggestion to use a thermo-insulating material for the insert was mine.

[Frits Overmars]

hey frits in the photo with your hand over the engine top (previous pg), why is the carb not at the same angle as the cylinder inlet ? is it only because there isnt a suitable carb that can operate at that steep downward angle or is it some other reason ?

That downward angle isn't steep at all and the carb could easily be fitted with a straight inlet rubber; it would even improve the flow somewhat.
But then the carb and the airbox would be pointing upward in the same space where the driver's elbow is. Re-arranging a carb is easier than re-arranging an elbow.

[Peter1962]

Frits, the vast majority of the existing 2 stroke MX engines have case reed induction. In fact, the only cilinder reed engine is the yamaha YZ 250.
Is that a problem for 'rygerising' those existing engines ? Or can both types of engine be converted tot the ryger technique ?

[Frits Overmars]

Frits, the vast majority of the existing 2 stroke MX engines have case reed induction. In fact, the only cilinder reed engine is the yamaha YZ 250. Is that a problem for 'rygerising' those existing engines ? Or can both types of engine be converted tot the ryger technique ?

No problem as far as the Ryger principle is concerned. The only problem I can think of, is one of space: can you lodge the carb between the cylinder and the air filter on those machines?

[d2t]

Could there possibly be any tuning benefit to using a rotary valve intake or would that upset the Ryger timing somehow?

[breezy]

Breezy, I do have another crank system designed without a beam but that definitly stays in the draw for now, might be too embarrassing to show off
It allows for liner movement only, no centrifugal on the big end. Rod, bigend and piston can be one part, no gudgin pin at all. NO cams or cam rollers or cam tracks and is not single sided. BUT I would like to see it work before I open my big mouth!

would you think that if the highest combustion pressure occuring in this engine happend well after tcd that it would relieve the stress on the crank set up? trying to find out about hcci, has this been confirmed as whats going on in the engine?